A sweet potato also packs in more than a quarter of your daily needs for vitamins C and E, nutrients shown to prevent cell damage in athletes competing in extreme environments (altitude, heat, cold, pollution), as well as enhance muscle recovery after intense training. Sweet potatoes are also an excellent source of iron. Expand your intake of sweet potatoes beyond Thanksgiving by stirring them into chili, adding some to your favorite potato salad recipe, and adding shredded raw sweet potato into hamburger, meatloaf and meatball mixtures. Also, try using mashed sweet potato as a ravioli stuffing.
10. OrangesConsidered by many to be winter's most delicious fruit, oranges are rich in natural sugars for a quick energy boost, yet provide three grams of fiber for sustained energy. In addition, just one navel orange meets an entire day's requirement for vitamin C, while providing immune-enhancing flavonoids, helping to keep colds and flus at bay.
Your heart will also benefit from the folate in oranges. Opt for the whole orange (rather than juice), and be sure to eat the spongy inner layer that lies right under the colorful part of the skin to ensure you are receiving energy-sustaining fiber. Besides using oranges as a tasty, convenient snack, try adding sections of oranges to salads or smoothies, or using the juice as a marinade for meat.
Understanding Glycemic Index
The rate at which carbohydrates raise blood sugar and consequent insulin is measured by glycemic index. Carbohydrate-rich foods with a high-glycemic value enter the bloodstream rapidly, leading to a quick rise in blood glucose and the release of insulin.
A survey conducted at Harvard University's School of Public Health determined that 16 of the top 20 carbohydrates eaten by Americans are high glycemic. In fact, high-glycemic snack foods comprise 25 percent of the total caloric intake in the United States. Among the most popular are french fries, white bread, cereals with added sugar, soda, pizza and muffins.
In contrast, low-glycemic foods, which tend to be higher in fiber or contain protein, are converted into glucose slower than high-glycemic foods and, therefore, less insulin is needed to regulate blood sugar. About 50 to 70 percent of an athlete's total daily calorie intake should be from low-glycemic carbohydrates (three to five grams per pound of lean body weight). And no more than 10 percent of the calories eaten at rest should be from high-glycemic foods.
Good Choices: Enjoy sweet potatoes, old fashioned oatmeal, energy bars (Clif, PowerBar), beans, low-fat dairy foods, most fruits, 100 percent whole wheat or whole grain bread, oatmeal, nuts, whole wheat pasta, green peas, hummus and rice bran.
Foods to Avoid: Steer clear of sugared soft drinks, processed grains (white bread), french fries, pastries, scones, sugared cereals, syrup, whipped cream, chips and movie popcorn.
Kimberly Brown, M.S., R.D., is a registered sports dietitian and competitive endurance athlete based in San Diego, Calif. She provides nutritional counseling and meal planning to athletes worldwide.